Air leakage between a building and the outdoors can contribute significantly to occupant discomfort especially during seasons when outdoor air is loaded with allergens and moisture 1. Outdoor allergens usually find their way indoors through unfiltered infiltration of outside air into the building through small holes in the building envelope. This unwanted infiltration can be virtually eliminated and indoor air quality improved by using a comprehensive approach to sealing building shell air leaks and increasing proper ventilation. In short this means sealing holes in the building envelope, reducing HVAC system duct leakage, balance pressures inside the house, insuring adequate spot exhaust ventilation, and intermittently adding filtered, fresh outside air to the building.

42% of the air inside the average home is exchanged every hour with unfiltered air from the outdoors 2,3. This infiltration happens as a result of naturally occurring pressures within and outside the building pushing air through openings in the building’s exterior. As this outside air enters the house it carries with it any allergens that may be present, whether it be from the back yard, garage, or the crawl space. At best this unfiltered infiltration is useful for diluting indoor-created pollutants, venting out moisture, and replenishing oxygen levels that may be depleted due to combustion appliances in the winter. More often this air carries in more allergens, chemicals, mold spores, excess humidity, and heat than it carries out.

A multi-point blower door test can very accurately determine the Equivalent Leakage Area (EqLA) by taking thousands of measurements at various pressures induced on the house by a powerful and calibrated, computer controlled variable-speed fan. In addition to calculating the EqLA this same tool can also be used to locate the contributing holes in the building envelope.

1. The role and abatement of fungal allergens in allergic diseases. Robert K. Bush, Jay M. Portnoy The Journal of Allergy and Clinical Immunology - March 2001 (Vol. 107, Issue 3, Pages S430-S440)
2. U. S. Census Bureau (2002). American Housing Survey for the Charlotte Metropolitan Area: 2002. Retrieved March 17, 2009 from http://www.census.gov/prod/2003pubs/h170-02-63.pdf
3. Energy-Efficient Building: The best of fine homebuilding Taunton Press, 1999

What is AlBlock?
AlBlock is a home diagnostic and corrective service designed to help allergy sufferers breathe cleaner air inside their homes by reducing unwanted infiltration and increasing proper ventilation.

How does AlBlock work?
Outdoor allergens find their way indoors through the unfiltered infiltration of outside air into your home through small holes in the building envelope. Indoor air quality is improved by using the AlBlock process to find and seal these building shell air leaks, increase proper ventilation, and reduce pollutant sources.

What is the AlBlock process?

AlBlock is not a one-size-fits-all wonder product for your house.

AlBlock is a scientific approach to finding hidden defects and designing a comprehensive solution with regard to how your unique house works as a system. AlBlock is flexible and can be tailored to fit your budget.

1. A Performance Consultant meets with you to understand the problems you experience in your home.
2. A thorough home inspection is performed from the roof to the foundation.
3. The sum of all the holes in the home’s exterior shell (EqLA – see back panel) and the air leakage pathways are derived by a computer controlled fan.
4. Your unique AlBlock improvement strategy is developed from all the information gathered.
5. The corrective work is performed on your home when it’s convenient for you
6. Final inspection is performed to verify the improvement strategy implementation is affecting your home as desired.
7. Lastly the same consultant will meet with you again and teach you how to take advantage of your home’s new features

What are the benefits of AlBlock?

• Improved comfort
• Reduced outdoor allergens inside
• Reduced utility bills
• Reduced humidity in the summer
  • Reduces fungal germination
  • Reduces dust mite activity
• Increased humidity in the winter
  • Prevent dry skin
  • Prevent static electricity
• Makes your house more durable
• Stops carpet ghosting
• Improves HVAC efficiency and lifespan
• Adds value to your house
  • Reduce obselence
  • Receive AlBlock Certificate
• Makes your home a healthier place to live
• Fix Carbon Monoxide sources that may be present
• Screen for and eliminate possible
• Radon problems

AlBlock was discovered by Performance Point during the development and practice of energy efficiency programs on existing homes such as the Home Performance with ENERGY STAR program.

When Performance Point’s customers began realizing benefits beyond the scope of the efficiency work it became obvious that the greatest benefits were not energy usage but rather the improved comfort and air quality. AlBlock has been tailored to maximize these benefits.